Wireless-telephone transmitter.



J. P. McGARTY, K. DOUGLAS & F. P. HERRGUTH. WIRELESS TELEPHONE TRANSMITTER.

APPLICATION FILED MAY 17, 1909. RENEWED JULY 11, 1911.

1,044,798. Patented Nov. 19, 1912.

WITNESSES: INVENTOBS J% 7.1%? 2 @mZwZ zM JgZZM/ MW I ATTORQIVEY UNITED sTAT s PATENT OFFICE.

JOHN P. McCARTY AND KENDALL DOUGLAS, or OAKLAND, AND FRANK P. HERRGU'IH, or SAN FRANCISCO, CALIFORNIA, ASSIGNORS T0 UNIVERS L WIRELESS TELE- PHONE AND TELEGRAPH COMPANY, OF SAN FRANCISCO, CALIFORNIA, A coarom,

TION OF CALIFORNIA.

Specification of Letters Patent.

WIRELESS-TELEPHON E TRANSMITTER.

Patented NOV.,19, 1912 Application filed May 17, 1909, Serial No. 496,429. Renewed July 11, 1911. Serial No. 638,046.'

To all whom it may concern:

Be it known that we, JOHN P. MOCARTY and KENDALL DOUGLAS, both residing at Oakland, in the county of'Alameda, and

FRANK P. HERRGUTI-I, residing in the city and county of San F ranclsco, State of Callfornla, have invented a new and useful Improvement 1n lVlreless-Telephone 'lransmitters, of which the following is a specification in such full and clear terms as will' enable those skilled in the art to construct and use-the same. v

()ur invention relates to wireless telephony and has for its object to provide new and improved meansfor transmitting speech or tone between distant points through the intervening media and without interconnecting wires.

()ur object is attained by the means illustrated in the accompanying drawings, which comprise diagrammatic views of a transmitting device, the various figures showing various forms of applying our device.

The same numeral of reference marks the same part throughout the various views.

In general terms our invention consists in combining with an ordinary telephone transmitter, a Wheatstone bridge, a source of power, and a high tension transformer having a' spark gap.

Referring to the drawings, Figure 1 shows the four arms A, B, C, D, of a Wheatstone bridge. The resistances in all the three arms A, B, and C are adjustable and non-inductive. telephone transmitter t. A source of constant current is applied between the points 1 and 2; and from the points 3 and 4 leads 1 and 1 pass to the primary E of a transformer, the secondary F of which is connected with a spark gap s. In the circuit of the transformer primary, a condenser J is connected, said condenser being of the ordinary adjustable type. The bridge arms are then adjusted in any desired ratiorelas.

tively to the normal resistance of transmitter t, so .that ordinarily the potential dif ference between 3 and is zero. Varying the resistance of arm D by vibrating the diaphragm of the transmitter causes potential differences to appear between 3 and 4:, which come in waves corresponding with The arm D contains a the vibrations of the diaphragm and these transmitted through the surrounding media and received; by ordinary wireless telephone apparatus.

, Fig. 2 shows a view of our device having acontinuous metallic primary circuit, with out a condenser therein. Under some conditions the use of a condenser in this circuit would be contraindicated, and we wish it to be understood that the condenser may be dispensed with when expedient.

By the described arrangement, we are enabled to talk well over long distances.

Having described our invention what we claimas new and desire to secure by Letters Patent of the United States is:

.1. In a wireless telephone transmitter the I combination with a Wheatstone bridge, a

telephone, transmitter in, one of the arms thereof, a transformer having its primary connected across the bridge and its secondary connected with spark gap points, a direct current source connected with the remaining points of the bridge, and a condenser in said primary circuit.

. 2. In a wireless telephone transmitter, the I combination with a W'heatstone bridge, a

telephone transmitter forming one of the arms thereof,'of a high tension transformer having its primary bridging the same and its secondary provided with a spark gap.

3. In a wireless telephone transmitter," the combination with a transformer having a spark gap, of a Wheatstone-bridge electrically connected with said transformer having a telephone transmitter in one of its arms. 4. In a wireless telephone transmitter, having primary and secondary circuits,

means for varying the current in the primary circuit in correspondence with spoken words, consisting of a telephone transmitter arranged in one of the arms of a Wheatsto e bridge,the primary circuit including sai VVheatstone bridge.

5. In a wireless telephone transmitter, a

circuit including a Wheatstone bridge havmg the resistance of one of its arms variable,

and means for-varying said resistance in correspondence with spoken words.

5 6. In a wireless telephone transmitter, a primary circuit including a. Wheatstone bridge having a telephone transmitter in one of its arms. 1

7 In a wireless telephone transmitter, a

10 primary circuit including a Wheatstone bridge having atelephone transmitter in U one'of its arms, and a secondary circuit-having a spark gap.

8.111 a Wireless telephone transmitting 15 system, a radiating system, a normally balanced circuit system associated therewith, a 

